Giorgees Ifrodet, Affe Vanessa, Williams Islah, Desaulniers Jean-Paul
Faculty of Science, Ontario Tech University, 2000 Simcoe Street North, Oshawa, Ontario, Canada, L1G 0C5.
Chempluschem. 2024 Jun;89(6):e202400084. doi: 10.1002/cplu.202400084. Epub 2024 Mar 27.
Discovering new modifications for oligonucleotide therapeutics is essential for expanding its application to new targets and diseases. In this project, we focus on conjugating metaled ligands to short interfering RNAs (siRNAs) to investigate robust and simple conjugation methods for adding new properties such as real-time imaging to the siRNA. Here we report the chemical synthesis of novel Ga-(III)-corroles for their direct conjugation to siRNAs. Ga-(III)-corrole-siRNAs showed promising results when evaluated for gene silencing and live cell imaging. The knockdown activity of the firefly luciferase reporter gene was measured to evaluate gene silencing activity. Gene silencing studies from two 5'-Ga-(III)-labeled-siRNAs exhibited dose-dependent knockdown with ICs of 812.7 and 451.4 pM, which is comparable to wild-type (IC=439.7 pM) in the absence of red light, and ICs of 562.9 and 354.5 pM, which is also comparable to wild-type (IC=337.4 pM), in the presence of red light. In addition, imaging studies with Ga-(III)-corrole-modified siRNAs showed intense fluorescence in HeLa cells, highlighting that the Ga-(III)-corrole modification is an effective fluorophore for siRNA tracing and imaging. Moreover, the photodynamic activity of free base corrole vs the Ga-(III)-corrole was evaluated. Results show an increase of light cytotoxicity of the corrole ligand upon the addition of Ga-(III); however, no phototoxicity was observed when Ga-(III) ligands were linked to siRNA. In conclusion, Ga-(III)-corrole-siRNAs show promising results for applications in simultaneous real-time imaging and gene silencing.
发现寡核苷酸疗法的新修饰对于将其应用扩展到新靶点和疾病至关重要。在本项目中，我们专注于将金属化配体与小干扰RNA（siRNA）偶联，以研究用于给siRNA添加实时成像等新特性的强大而简单的偶联方法。在此，我们报告了新型Ga(III) - 卟啉的化学合成，用于其与siRNA的直接偶联。当对Ga(III) - 卟啉 - siRNA进行基因沉默和活细胞成像评估时，显示出了有前景的结果。通过测量萤火虫荧光素酶报告基因的敲低活性来评估基因沉默活性。来自两种5'-Ga(III)标记的siRNA的基因沉默研究显示出剂量依赖性敲低，在无红光时IC50分别为812.7和451.4 pM，与野生型（IC50 = 439.7 pM）相当，在有红光时IC50分别为562.9和354.5 pM，也与野生型（IC50 = 337.4 pM）相当。此外，用Ga(III) - 卟啉修饰的siRNA进行的成像研究在HeLa细胞中显示出强烈荧光，突出表明Ga(III) - 卟啉修饰是用于siRNA追踪和成像的有效荧光团。此外，还评估了游离碱卟啉与Ga(III) - 卟啉的光动力活性。结果表明，添加Ga(III)后卟啉配体的光细胞毒性增加；然而，当Ga(III)配体与siRNA连接时未观察到光毒性。总之，Ga(III) - 卟啉 - siRNA在同时进行实时成像和基因沉默应用方面显示出有前景的结果。
